dts: arm: npcx: Add `smb-wui` prop. to support wake-up from sleep

Add `smb-wui` property to support wake-up from sleep mode by START
condition when i2c is configured to target mode.

Signed-off-by: Alvis Sun <yfsun@nuvoton.com>
Signed-off-by: Mulin Chao <mlchao@nuvoton.com>